The MAGPUL Gen. 3 6.8 SPC Windowed Magazine is made specifically for LWRC Six8 rifles. These magazines come standard with an anti-tilt follower and window to see capacity. If you want to reduce the weight of your carbine this magazine is half the weight of a standard 6.8 SPC mag. These magazines have a very similar window to the standard 5.56 magazine from MAGPUL and are made from the same great polymer.